diff --git a/src/app/compute/compute.spec.ts b/src/app/compute/compute.spec.ts
new file mode 100644
index 0000000..3bbf6fa
--- /dev/null
+++ b/src/app/compute/compute.spec.ts
@@ -0,0 +1,13 @@
+import { compute } from './compute';
+
+describe('compute' , () => { //suite
+	it('should return 0 if input is negative', () => {
+		const result = compute(-1);
+		expect(result).toBe(0);
+	})
+
+	it('should increment if input is positive ' , () => {
+		const result = compute(1);
+		expect(result).toBe(2);
+	})
+})
diff --git a/src/app/compute/compute.ts b/src/app/compute/compute.ts
new file mode 100644
index 0000000..32f15d9
--- /dev/null
+++ b/src/app/compute/compute.ts
@@ -0,0 +1,5 @@
+export function compute(number){
+    if(number < 0)
+        return 0
+    return number + 1
+}